Image forming apparatus

ABSTRACT

An image forming apparatus includes a recording-medium stacking portion, a recording-medium ejection portion and a suctioning/exhausting unit. The recording-medium stacking portion is provided in a body portion or an upper portion of the image forming apparatus. The recording-medium stacking portion stacks recording media on which respective images are formed thereon. The recording-medium ejection portion ejects the recording medium in a recording-medium ejection direction to the recording-medium stacking portion. The suctioning/exhausting unit is located with respect to the recording-medium stacking portion in a direction, which is perpendicular to the recording-medium ejection direction and parallel to a surface of the recording medium staked on the recording-medium stacking portion. The suctioning/exhausting unit suctions air emitted from the recording medium, which is ejected from the recording-medium ejection portion onto the recording-medium stacking portion. The suctioning/exhausting unit exhausts the suctioned air through a filter.

BACKGROUND OF THE INVENTION Technical Field

The present invention relates to an image forming apparatus such as anelectrophotographic copying machine, printer, fax machine, ormultifunction machine provided with the combination of these functions,and more specifically, to an image forming apparatus capable of reducingdisagreeable odor and VOC exhausted out of the apparatus from anejection portion for ejecting recording media such as sheets of paper.

SUMMARY

According to an aspect of the invention, an image forming apparatusincludes a recording-medium stacking portion, a recording-mediumejection portion and a suctioning/exhausting unit. The recording-mediumstacking portion is provided in a body portion or an upper portion ofthe image forming apparatus. The recording-medium stacking portionstacks recording media on which respective images are formed thereon.The recording-medium ejection portion ejects the recording medium in arecording-medium ejection direction to the recording-medium stakingportion. The suctioning/exhausting unit is located with respect to therecording-medium stacking portion in a direction, which is perpendicularto the recording-medium ejection direction and parallel to a surface ofthe recording medium staked on the recording-medium stacking portion.The suctioning/exhausting unit suctions air emitted from the recordingmedium, which is ejected from the recording-medium ejection portion ontothe recording-medium stacking portion. The suctioning/exhausting unitexhausts the suctioned air through a filter.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will be described in detail basedon the following figures, wherein:

FIG. 1 is a schematic block diagram illustrating the main part of ablack and white multifunction machine as an image forming apparatusaccording to a first exemplary embodiment of the invention;

FIG. 2 is a block diagram illustrating the black and white multifunctionmachine as the image forming apparatus according to the first exemplaryembodiment of the invention;

FIG. 3 is a perspective external view illustrating the black and whitemultifunction machine as the image forming apparatus according to thefirst exemplary embodiment of the invention;

FIG. 4 is a schematic configuration view illustrating asuctioning/exhausting unit;

FIG. 5 is a timing chart illustrating a drive timing of an exhaust fan;

FIG. 6 is a schematic plan diagram illustrating the main part of theblack and white multifunction machine as the image forming apparatusaccording to the first exemplary embodiment of the invention;

FIG. 7 is a perspective external view illustrating a black and whitemultifunction machine as the image forming apparatus according to asecond exemplary embodiment of the invention;

FIG. 8 is a perspective external view illustrating a black and whitemultifunction machine as the image forming apparatus according to athird exemplary embodiment of the invention;

FIG. 9 is a perspective external view illustrating a black and whitemultifunction machine as an image forming apparatus according to afourth exemplary embodiment of the invention;

FIG. 10 is a perspective external view illustrating a black and whitemultifunction machine as an image forming apparatus according to a fifthexemplary embodiment of the invention;

FIG. 11 is a perspective external view illustrating an example of ablack and white multifunction machine as an image forming apparatus;

FIG. 12 is a perspective external view illustrating a black and whitemultifunction machine as an image forming apparatus according to a sixthexemplary embodiment of the invention;

FIG. 13 is a perspective external view illustrating the black and whitemultifunction machine as an image forming apparatus according to thesixth exemplary embodiment of the invention;

FIG. 14 is a schematic section view illustrating the black and whitemultifunction machine as an image forming apparatus according to thesixth exemplary embodiment of the invention;

FIG. 15 is a perspective external view illustrating a black and whitemultifunction machine as the image forming apparatus according to theseventh exemplary embodiment of the invention;

FIG. 16 is a schematic block configuration view illustrating the mainpart of the black and white multifunction machine as the image formingapparatus according to the seventh exemplary embodiment of theinvention;

FIG. 17 is a schematic configuration view illustrating a black and whitemultifunction machine as an image forming apparatus according to aseventh exemplary embodiment of the invention.

DETAILED DESCRIPTION

Exemplary embodiments of the invention will be described below withreference to the drawings.

First Exemplary Embodiment

FIG. 2 is a block diagram showing a black and white multifunctionmachine as an image forming apparatus according to a first exemplaryembodiment of the invention. This black and white multifunction machineis provided with the combination of the functions of a copying machine,printer, and fax machine.

As shown in FIG. 2, this black and white multifunction machine includesin its upper portion a scanner unit 3 as an image reading device and isconnected to a personal computer or the like (not shown) over a network(not shown).

The above black and white multifunction machine is adapted to reproducean image of a document read by the scanner unit 3, print an image basedon image data sent from the personal computer or the like, and functionas a fax machine sending and receiving image data over a telephone line.

As shown in FIG. 3, the black and white multifunction machine includesan operation panel 100 that allows a user to input an instruction to theblack and white multifunction machine.

In FIG. 2, reference number 1 denotes the body of the black and whitemultifunction machine. In the upper portion of the body of the black andwhite multifunction machine 1 are disposed an automatic document feeder(ADF) 2 for automatically transporting documents (not shown) separatelyon a one-by-one basis and the scanner unit 3 for reading an image of adocument transported by the automatic document feeder 2. The scannerunit 3 is configured to illuminate the document placed on a platen glass4 with a light source 5, project the reflected light image from thedocument in a scanning manner through a reduction optical system 11including a full rate mirror 6, half rate mirrors 7, 8, and an imaginglens 9 onto an image reading element 10 such as a CCD, and read thereflected light color image of the document with the image readingelement 10 at a predetermined dot density (16 dot/mm, for example).

The reflected light image of the document read by the scanner unit 3 issent to an image processing system (IPS) 12, for example, in the form of3-color reflectance data of red (R), green (G), and blue (B), eachhaving 8-bit resolution. The image processing system 12 provides, asrequired, predetermined image processing on the image data of thedocument, including shading correction, misalignment correction,brightness/color space conversion, gamma correction, frame deletion, andcolor/motion editing, which will be described later. The imageprocessing system 12 also provides the predetermined image processing onimage data sent from the personal computer or the like (not shown).

Inside the body of the black and white multifunction machine 1 isdisposed a process cartridge 13 that integrally unitizes image formingmembers such as a photosensitive drum and works as a main part of animage forming unit for electrophotographically forming an image on asheet of paper. The process cartridge 13 is removably attached to thebody of the black and white multifunction machine 1 such that it can bereplaced with a new cartridge 13 by opening a cover (not shown)provided, for example, on the upper portion of the body of the black andwhite multifunction machine 1 when the photosensitive drum provided inthe process cartridge 13 has reached the end of its life or the toner ina developing unit has been consumed.

As shown in FIG. 2, the process cartridge 13 is configured to have aphotosensitive drum 14 as an image carrier, a charging roll 15 ascharging means, a developing unit 16 as developing means, and a cleaningunit 17.

The photosensitive drum 14 employs, for example, a conductive cylindercoated with an organic photoconductor (OPC) and adapted to be driven bydriving means (not shown) at a predetermined rotational speed along thedirection indicated by the arrow. The surface of the photosensitive drum14 is uniformly charged to a predetermined electrical potential by thecharging roll 15 as charging means, and then exposed with an image by alaser writing unit 18 as exposing means to form an electrostatic latentimage according to the image information. The laser writing unit 18 isconfigured to modulate a semiconductor laser 19 based on the image datahaving undergone the predetermined image processing in the imageprocessing system 12, and project a laser beam LB emitted from thesemiconductor laser 19 on the photosensitive drum 14 in a scanningmanner through an imaging optical system including a collimator lens 20,a reflective mirror 21, a polygonal mirror 22, an f-θ lens 23 and thelike to form the electrostatic latent image on the surface of thephotosensitive drum 14. The electrostatic latent image formed on thephotosensitive drum 14 is developed by a developing roll 24 in thedeveloping unit 16 containing a mono-component developer (toner) to forma toner image. Of course, the developing unit 16 may use a two-componentdeveloper.

As shown in FIG. 2, the toner image formed on the photosensitive drum 14is transferred onto a recording sheet 26 as a recording medium by atransfer roll 25 as transferring means. The recording sheet 26 is fed bya feed roll 27 from one of trays 28 of a plurality of feed cassettes,and transported separately on a one-by-one basis by a separation roll 29and retard roll 30 along a sheet transport path 32 through transportrolls 31 to resist rolls 33, and temporarily stays there. The recordingsheet 26 is then transported to the surface of the photosensitive drum14 by the resist roll 33 in synchronization with the toner image formedon the photosensitive drum 14, and the toner image is transferred by thetransfer roll 25 from the photosensitive drum 14 onto the recordingsheet 26.

In the lower portion of the body of the exemplary black and whitemultifunction machine 1 shown in FIG. 2 are disposed two sets of feedcassette trays 28.

The recording sheet 26 on which the toner image was transferred proceedsaway from the photosensitive drum 14 to a fixing unit 35 through atransport guide 34. The recording sheet 26 then undergoes a fixingprocess in which heat and pressure are applied by a heat roll 36 and apressure roll 37 in the fixing unit 35. Subsequently, the recordingsheet 26 is guided along a sheet transport path 39 formed of thetransport guide 34 and a transport shoot 38, redirected about 90degrees, and ejected by sheet ejection rolls 41 disposed close to asheet ejection portion 40 on a sheet ejection tray 42 as arecording-medium stacking portion outside the machine, which thencompletes a sequence of the image forming process.

In the above black and white multifunction machine, the scanner unit 3is provided in the upper portion of the body of the black and whitemultifunction machine 1, and the sheet ejection tray 42 as arecording-medium stacking portion is provided inside a body portion ofthe black and white multifunction machine formed of the body of theblack and white multifunction machine 1 and the scanner unit 3.

After the toner image transfer process completes, the cleaning unit 17removes residual toner or the like from the surface of thephotosensitive drum 14 to make the surface ready for the next imageforming process.

In the image forming apparatus according to this exemplary embodiment,an image forming apparatus includes a recording-medium stacking portion,a recording-medium ejection portion and a suctioning/exhausting unit.The recording-medium stacking portion is provided in a body portion oran upper portion of the image forming apparatus. The recording-mediumstacking portion stacks recording media on which respective images areformed thereon. The recording-medium ejection portion ejects therecording medium in a recording-medium ejection direction to therecording-medium stacking portion. The suctioning/exhausting unit islocated with respect to the recording-medium stacking portion in adirection, which is perpendicular to the recording-medium ejectiondirection and parallel to a surface of the recording medium stacked onthe recording-medium stacking portion. The suctioning/exhausting unitsuctions air emitted from the recording medium, which is ejected fromthe recording-medium ejection portion onto the recording-medium stackingportion. The suctioning/exhausting unit exhausts the suctioned airthrough a filter.

That is, as shown in FIGS. 1 to 3, the above black and whitemultifunction machine is provided with a suctioning/exhausting unit 60on the rear side of the sheet ejection tray 42, which serves as arecording-medium stacking portion, that is, in a direction perpendicularto the sheet ejection direction and parallel to the surface of the sheetof paper. The suctioning/exhausting unit 60 suctions the air dischargedfrom both the sheet ejection portion 40 and the sheet ejection tray 42and exhausts the suctioned air through the filter. Thesuctioning/exhausting unit 60 is disposed, for example, in a region ofthe sheet ejection tray 42, which is the vicinity of and above the sheetejection portion 40 including the sheet ejection rolls 41. Of course,the suctioning/exhausting unit 60 may not be disposed in the region ofthe sheet ejection tray 42, which is the vicinity of and above the sheetejection portion 40, but may be disposed in a region in the vicinity ofand rearward of the sheet ejection portion 40.

As shown in FIGS. 2 and 3, the black and white multifunction machine isprovided with a box-like support portion 50 on the rear side of thesheet ejection tray 42 functioning as a recording-medium stackingportion in the direction perpendicular to the sheet ejection direction.The box-like support portion 50 supports the scanner unit 3 and connectsthe scanner unit 3 and the body of the black and white multifunctionmachine 1. The support portion 50 is a generally L-shaped memberextending across the rear side and left side of the scanner unit 3. Aportion 51 of the support portion 50 located on the left side of thescanner unit 3 is integrally formed with a sheet ejection unit 52 of thebody of the black and white multifunction machine 1. The support portion50 houses members for providing image processing functions, includingthe predetermined image processing, image editing and image dataaccumulation for images read by the scanner unit 3 or image data sentfrom the personal computer or the like (not shown).

As shown in FIGS. 2 and 3, the suctioning/exhausting unit 60 includes aninlet 62 with louvers 55 provided on the front side of the supportportion 50. As shown in FIG. 1, the inlet 62 communicates with a short,generally rectangular duct 61 protruding toward the rear side of thesupport portion 50. The duct 61 defines a compartment separate from theinterior of the support portion 50 and is configured to exhaust the airsuctioned from the inlet 62 out of the image forming apparatus throughan outlet provided on the opposite side of the duct 61. The duct 61 doesnot communicate with the inside of the black and white multifunctionmachine 11. The duct 61 suctions external air only through the inlet 62and exhausts the suctioned air from an outlet disposed on an oppositeside to the duct 61.

In consideration of the apparatus configuration, thesuctioning/exhausting unit 60 including the duct 61 and the like isdisposed in the support portion 50 that connects the scanner unit 3 andthe body of the black and white multifunction machine 1. Alternatively,the suctioning/exhausting unit 60 may of course be configured separatelyindependent of the support portion 50 or the like.

As shown in FIGS. 1 and 4, the duct 61 houses an exhaust fan 65 and afilter 66 and has a rear surface 67 that is fully open to outside. Theinterior of the exhausting portion 64 includes partition walls 68 toprovide a narrow space on the upstream side of the exhaust fan 65 sothat the exhaust fan 65 collets the air passing through the inlet 62,and the air exhausted by the exhaust fan 65 slightly spreads out and isexhausted outside from louvers 55 provided on the rear surface 67 of theexhausting portion 64.

The filter 66 is formed of at least two of the following filters: afilter for removing odor, a filter for adsorbing or decomposing volatileorganic compounds, and a filter for adsorbing or decomposing ozone. Inthis exemplary embodiment, the filter 66 is formed of the filter forremoving odor and the filter for adsorbing or decomposing volatileorganic compounds.

As will be described below, the black and white multifunction machineconfigured as above according to this exemplary embodiment caneffectively remove disagreeable odor, volatile organic compounds and thelike discharged from the region in the vicinity of the ejection portionof the apparatus in the direction perpendicular to the sheet ejectiondirection without extra cost, increased noise, greater powerconsumption, bulkier apparatus or the like.

That is, as shown in FIG. 2, in the black and white multifunctionmachine according to this exemplary embodiment, the image of thedocument read by the scanner unit 3 undergoes the predetermined imageprocessing provided by the image processing unit 12 and is used to formthe toner image on the photosensitive drum 14 in the process cartridge13 that forms the main part of the image forming unit, and then thetoner image formed on the photosensitive drum 14 is transferred onto therecording sheet 26 by the transfer roll 25.

Then, the toner image transferred as a whole image onto the recordingsheet 26 is fixed on the sheet 26 by heat and pressure of the fixingunit 35. The thus processed recording sheet 26 is ejected by sheetejection rolls 41 from the sheet ejection portion 40 onto the sheetejection tray 42 provided in the upper portion of the body of the blackand white multifunction machine 1, which then completes the imageforming process.

When the toner image is fixed onto the recording sheet 26 by heat andpressure of the fixing unit 35, disagreeable odor and volatile organiccompounds (VCO) are produced from the toner and the like. As shown inFIG. 1, the odor and volatile organic compounds (VCO) produced from thetoner and the like is discharged out of the body of the black and whitemultifunction machine 1 along with the recording sheet 26 when therecording sheet 26 is ejected from the sheet ejection portion 40 ontothe sheet ejection tray 42 provided in the upper portion of the body ofthe black and white multifunction machine 1.

As shown in FIG. 1, the recording sheet 26 is ejected from the sheetejection portion 40 located above the inclined sheet ejection tray 42toward the sheet ejection tray 42 and drops due to its own weight intothe sheet ejection tray 42. There is a layer of air between the sheetejection tray 42 and the recording sheet 26 ejected from the sheetejection portion 40 onto the sheet ejection tray 42. As shown in FIG. 1,the air above the sheet ejection tray 42 is moved in the direction,which is perpendicular to the sheet ejection direction and parallel tothe surface of the sheet of paper, when the recording sheet 26 drops dueto its own weight on the sheet ejection tray 42.

In this exemplary embodiment, as shown in FIG. 1, thesuctioning/exhausting unit 60 provided with the inlet 62 is disposed onthe rear side of the sheet ejection tray 42, that is, in the direction,which is perpendicular to the sheet ejection direction and parallel tothe surface of the sheet of paper, and the exhaust fan 65 provided inthe suctioning/exhausting unit 60 is driven.

In this exemplary embodiment, as shown in FIG. 7, the exhaust fan 65 isdriven in synchronization with the start of the image forming operation,that is, in the example shown in the figure, in synchronization with thehigh state of a fuser fan in the fixing unit. The exhaust fan 65 is alsoconfigured such that it continues to operate for a predetermined timeperiod (about 30 seconds, for example) after the image forming operationhas completed.

The disagreeable odor and volatile organic compounds produced when theunfixed toner image is fixed on the recording sheet 26 in the fixingunit 35 are discharged from the sheet ejection portion 40 out of thebody of the black and white multifunction machine 1 as the recordingsheet 26 moves. However, according to the above configuration, as shownin FIGS. 1 and 6, the odor and volatile organic compounds dischargedfrom the sheet ejection portion 40 and sheet ejection tray 42 out of thebody of the black and white multifunction machine 1 are immediatelysuctioned through the inlet 62 of the suctioning duct 61 disposed on therear side of the sheet ejection tray 42, that is, in the direction,which is perpendicular to the sheet ejection direction and parallel tothe surface of the sheet of paper. The suctioned air is then filteredout through the filter 66 provided in the suctioning duct 61, anddischarged through the exhaust fan 65 out of (to the rear side of) thebody of the black and white multifunction machine 1.

Thus, in the black and white multifunction machine according to thisexemplary embodiment, the suctioning/exhausting unit 60 is disposed onthe rear side of the sheet ejection tray 42, that is, in the direction,which is perpendicular to the sheet ejection direction and parallel tothe surface of the sheet of paper. The exhaust fan 65 provided in thesuctioning duct 61 of the suctioning/exhausting unit 60 is driven toefficiently suction the disagreeable odor and volatile organic compoundsfrom the inlet 62 of the suctioning duct 61. The suctioned disagreeableodor and volatile organic compounds are filtered out through the filter66, and then discharged through the exhaust fan 65 out of the body ofthe black and white multifunction machine 1. Therefore, the above blackand white multifunction machine can efficiently suction and remove thedisagreeable odor and volatile organic compounds emitted from therecording sheet 26 and the like and discharge them out of the machine byproviding the suctioning/exhausting unit 60 on the rear side of thesheet ejection tray 42 of the body of the black and white multifunctionmachine 1, that is, in the direction, which is perpendicular to thesheet ejection direction and parallel to the surface of the sheet ofpaper.

Accordingly, it is possible to effectively remove the disagreeable odor,volatile organic compounds and the like discharged from the region inthe vicinity of the ejection portion of the image forming apparatus inthe direction, which is perpendicular to the sheet ejection directionand parallel to the surface of the sheet of paper, without the exhaustfan 65 being made larger or its rotational speed being increased, thatis, without increase in cost, noise, power consumption, or size of theapparatus as is the case with the black and white multifunction machinein which the suctioning/exhausting unit 60 located away from the sheetejection tray 42 of the body of the black and white multifunctionmachine 1 suctions the odor and volatile organic compounds emitted fromthe recording sheet 26 and the like.

Second Exemplary Embodiment

FIG. 7 shows a second exemplary embodiment of the invention. In thefollowing description, the same parts as those of the first exemplaryembodiment have the same characters. The second exemplary embodiment isconfigured such that the recording-medium stacking portion includes acover member that closes at least one of surfaces of the image formingapparatus except a side of an operation unit.

Specifically, as shown in FIG. 7, the black and white multifunctionmachine according to the second exemplary embodiment is configured suchthat a cover member 80 closes the downstream side of the sheet ejectiontray 42 in the sheet ejection direction. Thus, the support portion,sheet ejection portion, and the cover member 80 covers the rear, leftand right sides of the upper portion of the sheet ejection tray 42 toform a barrel-like space, resulting in covering all surfaces of thesheet ejection tray 42 except the surface of the operation unit (thefront side) of the black and white multifunction machine.

The cover member 80 is desirably formed of a transparent plastic plate,making the recording sheet 26 ejected on the sheet ejection tray 42visible from outside of the image forming apparatus.

By providing the cover member 80 that closes the downstream side of thesheet ejection tray 42 in the sheet ejection direction, the cover member80 prevents disagreeable odor, volatile organic compounds and the likefrom being discharged outside from the downstream side of the sheetejection tray 42 in the sheet ejection direction. Therefore, the odor,volatile organic compounds and the like above the sheet ejection tray 42can be suctioned and removed by the suctioning/exhausting unit 60.

Since other arrangements and effects of this exemplary embodiment aresimilar to those of the above exemplary embodiment, the descriptionthereof will be omitted.

Third Exemplary Embodiment

FIG. 8 shows a third exemplary embodiment of the invention. In thefollowing description, the same parts as those of the first exemplaryembodiment have the same characters. The third exemplary embodiment isconfigured such that the suctioning/exhausting unit is located on oneside of the recording-medium stacking portion in the direction, which isperpendicular to the ejection direction and parallel to the surface ofthe recording medium, and that the image forming apparatus furtherincludes a cover member disposed on an opposite side to thesuctioning/exhausting unit to block the air from being discharged.

Specifically, as shown in FIG. 8, in the black and white multifunctionmachine according to the third exemplary embodiment, thesuctioning/exhausting unit 60 is provided only on one side of the sheetejection tray 42 in the direction, which is perpendicular to the sheetejection direction and parallel to the surface of the recording medium,that is, on the rear side of the sheet ejection tray 42. A blockingmember 81 formed of a triangular plate is provided on the opposite sideto the suctioning/exhausting unit 60 (the front side) to block the airfrom being discharged.

The blocking member 81 formed of the triangular plate is thus providedon the opposite side from the suctioning/exhausting unit 60 (the frontside) to block the air from being discharged. Therefore, when the sheet26 drops on the sheet ejection tray 42, disagreeable odor and volatileorganic compounds emitted from the recording sheet 26 can be preventedfrom leaking to the front side. The odor and volatile organic compoundsblocked by the blocking member 81 return to the rear side and aresuctioned and removed by the suctioning/exhausting unit 60.

Since other arrangements and effects of this exemplary embodiment aresimilar to those of the above embodiments, the description thereof willbe omitted.

Fourth Exemplary Embodiment

FIG. 9 shows a fourth exemplary embodiment of the invention. In thefollowing description, the same parts as those of the first exemplaryembodiment have the same characters. The fourth exemplary embodiment isconfigured such that an additional stacking portion on which recordingmedia are ejected can be added to in an upper portion of therecording-medium stacking portion, and that the suctioning/exhaustingunit suctions and exhausts air emitted from both the recording-mediumstacking portion and the additional stacking portion.

Specifically, as shown in FIG. 9, in the black and white multifunctionmachine according to the fourth exemplary embodiment, a bin tray 82functioning as the additional stacking portion is added to the sheetejection tray 42 functioning as the recording-medium stacking portion,and a second sheet ejection portion 83 for ejecting sheets of paper isadded above the sheet ejection portion 40. This configuration enablesprinted recording sheets 26 to be ejected onto the sheet ejection tray42; copied recording sheets 26 to be ejected onto the bin tray 82;copied recording sheets 26 to be sorted and ejected accordingly onto thesheet ejection tray 42 and bin tray 82; or printed or copied recordingsheets 26 to be ejected on the sheet ejection tray 42 and faxed sheetsto be ejected onto the bin tray 82.

As shown in FIG. 9, the above black and white multifunction machine isconfigured such that the air is suctioned from both the sheet ejectiontray 42 and bin tray 82 into the inlet 62 of the suctioning/exhaustingunit 60 and exhausted therethrough.

Since other arrangements and effects of this exemplary embodiment aresimilar to those of the above embodiments, the description thereof willbe omitted.

Fifth Exemplary Embodiment

FIG. 10 shows a fifth exemplary embodiment of the invention. In thefollowing description, the same parts as those of the first exemplaryembodiment have the same characters. The fifth exemplary embodiment isconfigured such that the recording-medium stacking portion is located inthe upper portion of the image forming apparatus, and that the imageforming apparatus further includes a cover member that closes at leastone surface of the recording-medium stacking portion.

Specifically, as shown in FIGS. 10 and 11, the black and whitemultifunction machine according to the fifth exemplary embodiment is notprovided with the scanner unit 3 in the upper portion of the body of theblack and white multifunction machine 1, but the sheet ejection tray 42functioning as the recording-medium stacking portion in the upperportion of (the body of) the black and white multifunction machine.

In the fifth exemplary embodiment, cover members 84, 85, 86, and 87 areprovided to close the rear side, upper right side, upper left side, andtop side of the sheet ejection tray 42, respectively. The top side covermember 87 is openable.

Also in a printer without the scanner unit 3, these covers can preventdisagreeable odor and volatile organic compounds emitted from therecording sheet 26 around the sheet ejection tray 42, from leaking tothe front side.

Since other arrangements and effects of this exemplary embodiment aresimilar to those of the above embodiments, the description thereof willbe omitted.

Sixth Exemplary Embodiment

FIG. 12 shows a sixth exemplary embodiment of the invention. In thefollowing description, the same parts as those of the first exemplaryembodiment have the same characters. In the apparatus according to thesixth exemplary embodiment, the recording-medium stacking portion islocated in the upper portion of the image forming apparatus. Thesuctioning/exhausting unit suctions air from both the ejection directionand the direction, which is perpendicular to the ejection direction andparallel to the surface of the recording medium.

In the sixth exemplary embodiment, the image forming apparatus includesa duct member that extends through front, rear and top sides of therecording-medium stacking portion to surround a region in a vicinity ofthe recording-medium ejection portion

Specifically, as shown in FIGS. 12 and 13, the black and whitemultifunction machine according to the sixth exemplary embodiment is notprovided with the scanner unit 3 in the upper portion of the body of theblack and white multifunction machine 1, but the sheet ejection tray 42functioning as the recording-medium stacking portion in the upperportion of (the body of) the black and white multifunction machine aswith the fifth exemplary embodiment.

In the sixth exemplary embodiment, the suctioning/exhausting unit 60 isprovided to suction from both sides of the sheet ejection tray 42 in thedirection, which is perpendicular to the sheet ejection direction andparallel to the surface of the sheet of paper. A gate-shaped duct member90 is disposed at a base end portion of the sheet ejection tray 42 tosurround the front and rear sides of the base end portion of the sheetejection tray 42 in the direction, which is perpendicular to the sheetejection direction and parallel to the surface of the sheet of paper, aswell as the top side of the base end portion of the sheet ejection tray42. The duct member 90 does not communicate with the inside of the blackand white multifunction machine 1. The duct member 90 suctions externalair only through an inlet 92 and exhausts the suctioned air from anoutlet disposed on an opposite side to the inlet 92.

As shown in FIG. 14, the duct member 90 has inlets 91 and 92 on thefront side of the sheet ejection tray 42 in the direction, which isperpendicular to the sheet ejection direction and parallel to thesurface of the sheet of paper, and at the positions corresponding to theupper portion of the first sheet ejection portion 40 and to a sideportion or downward portion of the second sheet ejection portion 83respectively. The duct member 90 also has an inlet 93 on the rear sideof the sheet ejection tray 42 in the direction perpendicular to thesheet ejection direction and at the position corresponding to a sideportion or downward portion of the second sheet ejection portion 83.

This allows the inlets 91, 92 and 93 of the duct member 90 toeffectively suction disagreeable odor and volatile organic compoundsemitted from the recording sheet 26 onto the sheet ejection tray 42.

Since other arrangements and effects of this exemplary embodiment aresimilar to those of the above embodiments, the description thereof willbe omitted.

Seventh Exemplary Embodiment

FIG. 15 shows a seventh exemplary embodiment of the invention. In thefollowing description, the same parts as those of the first exemplaryembodiment have the same characters. In the seventh exemplaryembodiment, the second sheet ejection portion can eject recording sheetsupside down by counterrotating the sheet ejection rolls therein.

Specifically, as shown in FIGS. 15 to 17, in the black and whitemultifunction machine according to the seventh exemplary embodiment, aswitching lever 95 can switch the sheet transport path 39 between thefirst sheet ejection portion 40 and the second sheet ejection portion83. The second sheet ejection portion 83 can eject the recording sheet26 by sheet ejection rolls 97 through the second sheet transport path 96onto the sheet ejection tray 82 of the second sheet ejection unit 83.Also, the second sheet ejection portion 83 is configured such that whilethe sheet ejection rolls 97 catch the rear end of the recording sheet 26therebetween, the sheet ejection rolls 97 can be counterrotated totransport the recording sheet 26 along the second sheet transport path96 in the opposite direction with the rear end of the recording sheet 26being the leading edge and the switching lever 95 switches the transportpath to eject the recording sheet 26 upside down on the sheet ejectiontray 42.

In the seventh exemplary embodiment, as shown in FIG. 15, when therecording sheet 26 is temporarily ejected on the sheet ejection tray 82before reversing it, the inlet 62 of the suctioning/exhausting unit 60suctions and removes disagreeable odor and volatile organic compoundsemitted from the recording sheet 26.

As shown in FIG. 16, a plurality of filters 67 ₁ and 67 ₂ with the sameor different filtering characteristics may be located in tandem in thesuctioning/exhausting unit 60.

Since other arrangements and effects of this exemplary embodiment aresimilar to those of the above embodiments, the description thereof willbe omitted.

The foregoing description of the embodiments of the present inventionhas been provided for the purposes of illustration and description. Itis not intended to be exhaustive or to limit the invention to theprecise forms disclosed. Obviously, many modifications and variationswill be apparent to practitioners skilled in the art. The embodimentswere chosen and described in order to best explain the principles of theinvention and its practical applications, thereby enabling othersskilled in the art to understand the invention for various embodimentsand with the various modifications as are suited to the particular usecontemplated. It is intended that the scope of the invention be definedby the following claims and their equivalents.

1-11. (canceled)
 12. An image forming apparatus comprising: arecording-medium stacking portion provided in a body portion or an upperportion of the image forming apparatus, the recording-medium stackingportion that stacks recording media on which respective images areformed thereon; a recording-medium ejection portion that ejects therecording medium in a recording-medium ejection direction to therecording-medium stacking portion; and a suctioning/exhausting unitlocated with respect to the recording-medium stacking portion in adirection, which is perpendicular to the recording-medium ejectiondirection and parallel to a surface of the recording medium stacked onthe recording-medium stacking portion, the suctioning/exhausting unitthat includes an inlet on a rear side which is perpendicular to therecording-medium ejection direction of the recording-medium stackingportion and parallel to a surface of the recording-medium, and an outleton a back surface of the image forming apparatus.